Just a comment regarding the practice of checking to see if a film contains a valid notice, that is widely advocated in this forum. The 1978 copyright law added several exceptions to the notice requirement that allowed films published without a valid notice be be excused:

- Works published after 1978 without a notice had five years to include a valid notice, in which case the copyright would hold.

- The law states that the copyright notice must have been on the film when it was published. But it also states that if the copyright was absent on a small number of films, OR if a party who was under contractualy obligation to include the notice, failed to do so, the film is not automatically public domain.

Additionally, unless you have digitized the film yourself from an original print, there is little chance that you will know what was on the original print. There are many cases where a film that was published without a valid notice was reissued later with a valid notice, presumably to discourage its diffusion into the Public Domain, although that film is in fact Public Domain. Sometimes doing so could actually have some legal basis, for example the film has been revised, by adding a new soundtrack or new material (e.g. outtakes from the original that were never published) in order to create a copyrightable derivative product. So you may find a print that has a valid notice and is in fact under copyright, whereas the original is Public Domain. In this case the only difference would be a few scenes or some music. But in those specific cases, the copyright registration would need to specify what was changed.

IMHO deciding that a film is PD based on lack of copyright notice without having seen at least one original print, is the most difficult way to determine wheter or not a film is actually PD. IN the book "The Public Domain", by Attorney Stephen Fishman, he says,

"People often place copyright notices on public domain works they copy and/or resell to the public...the penalties for placing a notice on a public domain work are very small."

Also, re: Orphan works, which are works where the copyright holder cannot be found, to ask for permission to publish the work. This is a hot topic in copyright law, primarily due to the google book digitization project. But it has not been decided whether or not orphan works can be used without penalty. And the proposed legislation would require that the user pay some small fee (determined by the orphan works law) in the event that the copyright holder showed up at some point in the future. I'm all for orphan works. At least such works could actually start to make money if they pass such a law.